1 Answer

Try using the earphones with the microphone attachment to make and receive calls to verify that you can be heard OK.

If you can be heard OK then there is a problem with the phone's internal microphone.

It is either faulty, has come loose from the systemboard or perhaps the voice inlet hole has become blocked.

To check out this last possibility, use a strong light and a magnifying glass to inspect the phone's voice inlet hole.

This is to be found on the bottom edge of the phone.

It it appears to be blocked, DO NOT use a pin etc. to try and clear the blockage. You might damage the microphone which is directly behind it. Try a vacuum cleaner, using short bursts to try and suck the obstruction out of the hole.

If it is clear upon initial inspection, then the phone will have to be opened to ascertain the problem with the microphone. As you haven't stated the model number of the phone, you could try looking on the ifixit website to see if there is a repair guide for your model. At least enough to open the phone to check if the microphone is loose. Here is a link ZTE Phone. If there is not a guide for your model you could check on places such as YouTube etc. Look for ZTE (your model) teardown or screen replacement to find videos of how to open the phone.

If you find the process of repairing your phone too daunting, contact a reputable, professional mobile phone repair service and ask for a quote to repair the phone.

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